Adaptive equalizers, such as normalized least mean square (NLMS) equalizers which are used in wireless transmit/receive units (WTRUs) and base stations, optimize their associated filter tap weights through an iterative procedure to reach a convergence. In the case of a pilot-directed equalizer, an error signal used to generate an update of the equalizer tap weights is derived by measuring the difference between the locally generated reference signal and the output of the equalizer. For a frequency division duplex (FDD) system, this amounts to supplying a reference signal that corresponds to a scrambled, spread and/or scaled pilot signal such that data symbols have the desired amplitude.
When operated at a chip rate, the output of a pilot-directed equalizer includes a plurality of signals superimposed on one another whereby only one of which is the pilot signal. Since the pilot signal is small in comparison to the total output signal, the error signal generated for filter coefficient adaptation includes mostly undesired signals.